DARPA Project NIMBUS
Lightning can cause delays in operations, disrupt communications, destroy assets, and generally pose a deadly threat to military personnel. While lightning has been studied intermittently for decades, critical questions remain about how and why lighting initiates, how it spreads, and how it attaches to objects. Also unclear is how lightning generates its ionospheric components such as elves, sprites, and gigantic blue jets, or how it ties into the global charging circuit.
Nimbus is a fundamental science program focused on obtaining a comprehensive understanding of the lightning process, its associated emissions (such as x-rays), and its ionospheric components to better protect troops, ordnance, and other military assets. This program will yield insights into other high-voltage, high-current electromagnetic phenomena.
This program will yield insights into other high-voltage, high-current electromagnetic phenomena. 
Experimental Set-up for Triggering Lightning: Bidders should fully describe how they would attempt to trigger lightning and list all potential pieces of equipment necessary to trigger lightning, as well as the equipment necessary to measure and characterize the processes governing lightning initiation, propagation, and attachment. 
The Pentagon Launches Plan to Master Lightning
Another, somewhat more straightforward application of lightning, not mentioned as part of the DARPA project, is the possibility of creating a “lightning gun” – a weapon that shoots bolts of electricity. In fact, the Defense Department has funded work in this area. A Tuscon, Ariz., company called Applied Energetics (formerly Ionatron) has received a number of multimillion-dollar contracts from the Army and Navy to develop a lightning weapon that uses ultra-short laser pulses to channel electrostatic discharges. Another company, Xtreme Alternative Defense Systems, in Anderson, Ind., has built a prototype of a lightning gun, named StunStrike.
But don’t look to NIMBUS to yield a deployable death ray. DARPA says the project has a more benign goal: the protection of people and assets. 
Picatinny engineers set phasers to ‘fry’
PICATINNY ARSENAL, N.J. (June 21, 2012) -- Scientists and engineers at Picatinny Arsenal are busy developing a device that will shoot lightning bolts down laser beams to destroy its target. Soldiers and science fiction fans, you're welcome.
"We never got tired of the lightning bolts zapping our simulated (targets)," said George Fischer, lead scientist on the project.
The Laser-Induced Plasma Channel, or LIPC, is designed to take out targets that conduct electricity better than the air or ground that surrounds them. How did the scientists harness the seemingly random path made by lightning bolts and how does a laser help? To understand how the technology, it helps to get a brief background on physics.  
‘Dressed’ laser aimed at clouds may be key to inducing rain, lightning
The adage “Everyone complains about the weather but nobody does anything about it,” may one day be obsolete if researchers at the University of Central Florida’s College of Optics & Photonics and the University of Arizona further develop a new technique to aim a high-energy laser beam into clouds to make it rain or trigger lightning.
The solution? Surround the beam with a second beam to act as an energy reservoir, sustaining the central beam to greater distances than previously possible. The secondary “dress” beam refuels and helps prevent the dissipation of the high-intensity primary beam, which on its own would break down quickly. A report on the project, “Externally refueled optical filaments,” was recently published in Nature Photonics.
“Since we have control over the length of a filament with our method, one could seed the conditions needed for a rainstorm from afar. Ultimately, you could artificially control the rain and lightning over a large expanse with such ideas.“
Other possible uses of this technique could be used in long-distance sensors and spectrometers to identify chemical makeup. Development of the technology was supported by a $7.5 million grant from the Department of Defense.   
Teramobile: The first mobile terawatt laser in the world for atmospheric studies
The Teramobile system is the first mobile laser yielding 5 terawatts (TW) and 100 fs (10-13 s) pulses. It concentrates the state-of-the-art laser technology in a 20’ standard freight container, allowing field measurement campaigns.
The Teramobile laser permitted us to trigger and guide high-voltage (1 MV) discharges along filamentation in air. Those results open the way to active laser-control of lightning. 
Terawatt Laser Beam Shot in the Clouds Provokes Lightning Strike
American scientists tested a new ultra-high-power laser which provokes lightning. Scientists fired ultra-fast pulses from an extremely powerful laser thus sending several terawatts into the clouds to call down electrical discharges in storm clouds over the region.
The beams sent from the laser made channels of ionized molecules, also known as "filaments." It is worth mentioning that before the lighting strikes earth the filaments lead electricity through the clouds, playing the role of lightning rods.
Researchers generated filaments that are too short-lived to trigger a real lightning strike. According to the French and German scientists, the fast pulses sent from the laser will be able to provoke thunder strikes on demand.
It is worth mentioning that for the first time the proposal of using laser to provoke thunderbolts was made in 1970s, but back then there has been no laser powerful enough to achieve the goal.
In laboratories scientists widely use powerful lasers that can create terawatts of energy. But to make an experiment outdoors, researchers applied a new type of laser, named Teramobile, created by a teem of engineers from France and Germany. 
Laser Lightning Rod project
The LLR aims to investigate and develop a new type of lightning protection using a laser-based technique to stimulate the number of upward lightning flashes with the aim of transferring cloud charges to the ground and thus to influence the incidence of downward natural lightning.  
High-technology company TRUMPF and the University of Geneva have fired up a laser-based lightning rod at the top of Säntis mountain in Switzerland. Over the next few weeks, the researchers will be using this powerful system to conduct a series of weather experiments. Their aim is to control lightning from storm clouds and direct the strikes to places where they won’t cause any damage. TRUMPF laser engineer Clemens Herkommer – who works at TRUMPF Scientific Lasers in Unterföhring near Munich – has spent the past four years developing a one-of-a-kind super laser to make this goal a reality: “The laser lightning rod is currently one of the most powerful lasers in its class. By shooting a thousand laser pulses a second into the clouds, we can safely discharge the lightning and make the world that little bit safer!” says Herkommer. 
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